Closure device for metallic container opening



NQV. 27, 11934. J E A 11,982,144

CLOSURE DEVICE FOR METALLIC CONTAINER OPENING Filed Nov. '7, 1931Patented Nov. 27, I 1934 PATENT OFFICE CLOSURE DEVICE FOR METALLICCONTAINER OPENING John W. Shera, Chicago, 11]., assignor to AmericanFlange & Manufacturing 111., a corporation of Illinois Company, Chicago,

Application November 7, 1931, Serial No. 573,675

4 Claims.

My invention relates generally to metallic containers such as drums,barrels and the like, and it has to do particularly with sealed closuresfor the filling and discharge openings thereof. My invention isparticularly (although not exclusively) adapted for use in connectionwith containers suited for transportation and storage of oil, gasoline,and the like.

The principal object of my invention is to provide an improved closuredevice for containers of the foregoing character, which closure isadapted to positively seal the container fill or discharge openingagainst leakage and to maintain it sealed notwithstanding temperatureconditions and strains and stresses imposed in transporting and handlingthe container.

Another object is to provide a novel plug closure means of a characterpractically eliminating the possibility of the same loosening duringtransportation and handling, and which may be em ployed to efiectivelyclose the container opening after the sealed container has been opened.More particularly, my invention contemplates the use of a novel form ofclosure plug adapted to be concealed and rendered inaccessible by a sealcap, which plug detachably supports compressible gasket meanscooperating with the plug and the wall of the container opening toeffect a fluid-tight and air-tight closure. The gasket is so supportedby the plug that it yielding'ly opposes the final closing movement ofthe plug and, together with the seal cap, holds the plug againstloosening.

An additional object is to provide a novel form of seal-closureincluding a seal cap which is adapted to be secured in place in anair-tight leakproof manner and which is so applied and secured that itcannot be removed without such distortion and fracture thereof as torender it unfit for further use thereby preventing access to thecontainer contents without detection. Further, according to myinvention, the seal cap is provided with a tear-strip section which maybe broken through by a suitable tool and removed to facilitatedetachment of the cap as a whole.

Other objects and advantages will appear as this description progressesand by reference to the drawing in which,-- a

Figure 1 is a fragmentary top plan view of the head of a metalliccontainer employing one form of closure embodying my invention, certainof the parts being broken away to facilitate illustration;

Fig. 2 is an enlarged section taken substantially on line 2-2 of Fig. 1;

Fig. 3 is a sectional view in separated relation of the gasket shown inFig. 2 as supported by the closure plug;

Fig. 4 is a separated elevational view of the closure plug;

Fig. 5 is a sectional view in separated relation of the gasket shown inFig. 2 as disposed directly beneath the seal cap; and

Fig. 6 is a perspective view of the seal cap and illustrating a tearstrip section therein.

Referring particularly to the form of my invention shown in the drawing,the flat container head 10 is provided with a circular opening definedby an upstanding circular flange 11 struck, preferably, from the metalof the container head. The metal of the head 10. around the flange 11 ispressed upwardly to provide an annular boss 12 forming an internalpocket 13, the top of which serves as an annular seat 13 extendingaround the base of the opening formed by the flange 11. The seat portion13 takes, preferably, (but not necessarily) an octagonal shape in planoutline and it receives the similarlyshaped flange 14 of aninternally-threaded bushing 14, the cylindrical, upwardly-projectingportion 14 of which fits snugly within the annular flange 11. Theoutline shape of the bushing flange 14 and the seat 13 obviously,prevents rotation of the bushing when it is inserted in the containeropening. Also, the thickness of the bushing flange 14 is equal to thedepth of the pocket 13 so that its exposed surface lies flush with theinner fiat wall surface of the head; whereby the opening defined by thebushing is unobstructed and the entire contents of the container may bedrained. To firmly secure the bushing in place, its upper edge isgradually reduced in thickness and is extended upwardly and rolled overthe upper edge of the flange 11 forming a bead 15 thereat. When thebushing is secured as just described, a leak-proof joint is provided asbetween the bushing 14, the drum head and the flange 11; but, ifdesired, to further insure against leakage, a suitable gasket structure15 (or a suitable leak-proof material) may be interposed between thebushing flange 14 and the seat 13 (Fig. 2)

The opening in the bushing 14 may be closed by a metallic threaded plug16 which, preferably, takes the form best shown in Figs. 2 and 4.Specifically, the plug 16, which may be formed of any suitable material,has an externally threaded body adapted for engagement with the bushingthreads 14 and it is provided at its top with a flange or head portion16 The central portion of the plug is provided with anexteriorlyaccessible opening 16 of irregular outline shape adapted toreceive a suitable tool for screwing it into and out of the bushing 14.This plug is also provided with an annular groove 17 between its head 16and threaded body, which groove is adapted to receive and retain agasket 18 which may be formed of any suitable, compressible materialsuch as fibre, rubber, etc. The bushing 14, immediately above itsthreaded portion 14, and adjacent the head 15, is shaped to provide alaterally-extending seat 14 with which the plug groove 1'7 aligns whenthe plug 16 is in its closing position, and upon which the gasket 18 isseated and compressed.

With the foregoing arrangement, as the plug 16 is screwed into thebushing 14, a leak-proof, air-tight closure is provided. The latter partof the movement of the plug 16 into its closing position is yieldablyopposed by the gasket 18 and 1, preferably, arrange the closure parts sothat practically the entire final turn of the plug toward closingposition is so opposed by the gasket; whereby the gasket tends to gripand hold the plug in closing position and substantially a 'completeturrr'of the plug is required in order to loosen it to an extent whereit may turn freely in the bushing. This feature greatly reduces the.possibility of loosening of the plug to the point of leakagebyvibration, et cetera during transportation and handling.

For best results, the gasket 18 should be of a size to fit snugly in theplug groove. In the event of use of a fibre gasket of this characterwhich does not afford, in its normal condition, sufiicient resiliency topermit the same to be readily passed over the head of the plug, Ipropose to soften the preformed gasket by soaking the same in anysuitable liquid. This treatment, as will be readily understood, willpermit of sufficient expansion of the gasket in its softened form topass it over the plug head and, as the gasket assumes its original,normal unsoftened condition, it will shrink into close fit relation tothe plug groove.

While the closure structure just described may serve as eflicient meansfor closing the container opening during transportation and storage, itis highly desirable that additional seal means be employed which notonly protects the plug 16 against unauthorized removal or loosening, butwhich is also of a character readily and quickly informing one ofunauthorized tampering with the container closure. To this end, I employa relatively thin metallic seal cap 19, the side wall of which in itspre-securement form passes freely down over the beaded rim 15 of thebushing 14. Before the cap 19 is secured in place, a gasket 20 of anysuitable compressible material is applied thereto, preferably, in theposition shown in Fig. 2 so as to seat upon the upper rounded edge ofthe bead 15. It will benoted that the central portion of the top of thecap is slightly depressed forming an annular gasket-receiving pocket 19in which the gasket 20 is received and held against lateral displacementwhen the gasket is compressed upon the top of the bead by depression ofthe cap.

The plug 16 may be so related to the other "1 closure parts that, whenit is screwed fully inward, its head 16 is either flush with the top ofthe head, above the head or below it. However, in either case, the sealcap 19 is, preferably, so shaped and related to the plug that its .topseats upon the top of the plug (as shown in Fig. 2)

thereby serving as additional means for positively preventing looseningof the plug.

.In the securement of the cap, it isdepressed,

as a whole. upon the bead 15 to compress the gasket 20, and thissecurement-should be'eflected without the exertion of suchpressure onthe flange 11, bushing 14 and containerwall 10 in axial direction aswould tend to permanently distort the container wall which permanentdistortion, if itshould occur, would tend to destroy the usefulness ofthecontainer. To avoid such an objectionable condition, the cap. is,preferably, secured in place by contracting its skirt or side wall 19around and behind the bead 15 with a suitable tool acting inconjunctionwith the outer rounded side edge of the bead. To. facilitateuniform contraction-of the cap side wall, it may be corrugated orscalloped as clearly shown in Fig. 6; but, if desired, the cap sidewallmay be plain without hindering its attachment. One form of tool whichhas been disclosed to me, and

which I may employ, embodies radially movable elements adapted togrippingly engage the cap skirt forcing the same inwardly against andalong the outer rounded surface of the bead 15, the radial movement ofthe tool elements being converted into axial movement by the curvedsurface of the bead. For best results the cap may be depressed to anextent suificient to compress the 'gasket to one-half, or less, of itsoriginal thick ness.

In the finally-secured position of the cap, the free edge portion of itsskirt is firmly and uniformly seated upon the flange 11 behind the head15. In this manner, the cap is so securely fastened in place that itsremoval is exceedingly difficult. In fact, it cannot be removed withoutso distorting and fracturing the same that its further usefulness iswholly destroyed. This feature positively guards against undetected andunauthorized breaking of the seal. To facilitate removal of the cap, Iscore the top of the same along spaced lines 19 providing a tear-stripsection with an enlarged central portion'located directly above theopening 16 inthe plug 16. The enlarged portion of this tear-section iscrossscored as at 19 and this score line may readily be broken throughwith a screw driver or other suitably-pointed tool. The ends of thebroken away part may readily be grasped with a suitable tool to stripthe tear-section outwardly along the score lines 19 and through the capskirt or side wall, thereby loosening the cap so that it may be readilylifted from the closure structure.

The advantages to be derived from my invention are obvious from theforegoing. It provides a doubly-effective seal positively insuringagainst leakage and waste of the container contents under the most rigidtransportation and storage conditions. In fact, demonstration has shownthat the seal afforded by the cap alone is sufficiently strong andeffective to meet ordinary transportation, storage and pressureconditions.

Wherefore, if desired, the plug 16 may be'eliminated in certaininstances; and, in other instances, the plug'may be formed of wood,cork, or other'light weight material. Furthermore, the use of a closureplug formed of a lighter weight material, as provided by my invention,is an important factor from cost and tonnage stand-' points, andparticularly in marine shipping where tonnage limitations may beimposed; the closure plug-gasket assembly may well serve as a positiveclosure-seal means in the ordinary use of the container after the outerseal has been-broken; by mounting the gasket upon the closure plug, thegasket is always at hand for proper closure; and the closure-seal is ofan inexpensive character which may be readily and quickly applied.

While I have shown and described onlyoneform of structure embodying myinvention, it will be understood that changes in details and arrangementof parts may be made without departing from the spirit and scope of myinvention as defined by the claims which follow. For example, amongother things, the bushing 14 may be dispensed with and the outer end ofthe flange l1 rolled upon itself in such a way as to provide a beadcorresponding to the head 15; or the bead may be provided in any othersuitable manner. In that case, a closure plug may not be used; but, ifone is used, it may be friction-fitted and held against loosening by theseal cap. The score lines in the top of the seal cap may, if desired, beextended on through to the free edge of the cap skirt. In certain cases,the cap seal gasket 20 may be dispensed with, and in that event theskirt of the cap 19 may be crimped behind the bead 15 in any desiredmanner. The plug 16 and cap 19 may be so relatively shaped that the topof the cap may seat upon the top of the plug, the cap thereby serving asadditional means for preventing loosening of the plug.

I claim:

1. In structure of the class described, a container having an openingformed with an outwardly-extending cylindrical flange, a bushing fittingwithin said flange and having its outer end turned over the outer edgeof said flange for securingthe bushing within said flange, said turnedover outer edge forming a rounded bead, and leak-proof and tamper-proofseal means, including a metalliccap member having its cylindrical skirtencompassing said bead, said skirt being uniformly contracted throughoutits circumference snugly around said bead with its lower edge portionextending along substantially parallel with and entirely contacting withthe cylindrical flange below said head, and gasket means confined andcompressed between said bead and top of said cap member.

2. In a structure or the class described, a container having an openingformed with-an outwardly extending cylindrical flange, a threadedbushing fitting within said flange, and having its outer end above thethreads turned over the outer edge of said flange for securing thebushing within said flange, a gasket seat being formed at the top ofsaid threads, a plug having a threaded body with the outer end of theplug slightly enlarged, the plug having an annular groove between saidenlarged end and threaded part and a gasket in said groove, said gasketbeing compressed between said enlarged end and said seat and beingsubstantially confined below said enlarged end when said plug is screwedinto closing position, and leak-proof and tamper-proof seal meansincluding a metallic cap member having its cylindrical skirtencompassing said beaded end of the flange, said skirt portion beingentirely contracted around and behind said bead, and gasket meansconfined and compressed between said bead and the top of said cap memberand between said skirt portion and the enlarged end of said plug, thetop of said cap member contacting with the top of said plug when theplug and cap member are in closing positions.

3. In a structure of the class described, a container having an openingformed with an outwardly extending rigid cylindrical flange, the flangebeing provided with a bead at its outer edge, internal threads, and agasket seat at the top of the threads and within the upper end of theflange, a plug having a threaded body with the outer end of the plugslightly enlarged, a gasket carried by said plug under said enlargedend, said gasket being compressed between said enlarged end and saidseat and being substantially confined below said enlarged end when saidplug is screwed into closing position, and leak-proof and tamper-proofsealing means including a metallic cap having its cylindrical skirtcontracted 105 around said head with its lower edge portion entirelyengaging the flange in substantially parallel relation below said head,and a gasket conflned and compressed between said bead and the top ofthe cap vertically and between the skirt of the cap and the outer edgeof the enlarged end of the plug horizontally.

4. In structure of the class. described, a container having an openingformed with an outwardly-extending cylindrical flange, a bushing 5fitting within said flange and having its outer end turned over theouter edge of said flange for securing the bushing within said flange,said turned over outer edge forming a rounded bead, and leakprooi. andtamper-proof seal means including a 120 metallic cap member having itscylindrical skirt encompassing said head, said skirt being uniformlycontracted throughout its circumference snugly around said bead with itslower edge portion extending along substantially parallel with andentirely contacting with the cylindrical flange below said bead, andgasket means confined and compressed between said bead and top of saidcap member, said metallic cap member being provided with spaced scorelines providing a tear strip to 13 facilitate the removal of the cap.

JOHN W. SHERA.

